Tick Pods

8th March 2015

This is to relate a story from Margaret Binns. Margaret and her family lived on a large block on Wymond Rd. for about thirty years; for the past 12 years she has been the only resident. Margaret is a gardener and has befriended the wildlife.

Margaret became friendly with a number of roos, having fed them and treated them as pets. Around 2010, she noticed that many of them had large whitish lumps on various parts of their bodies, mostly in places where it was hard for them to scratch.

She realised these were ticks. They were of various sizes; the largest more than 2cm in size, mostly spherical but with some oblong features. Then, after a month or so, perhaps into November, she found one of these ‘pods’ on the ground. Thinking it was an unusual seed pod, she picked it up and noticed tiny legs on the sides. It was clearly a blown-up giant tick, almost transparent, with the remains of a snout and legs. She put it in a jar and noticed, as time progressed, that there was a mass of tiny dots inside. Weeks later, around Christmas time, the pod burst and a large number of the smallest pin-point-size ticks (pepper ticks) emerged in the jar. Unfortunately she was unsuccessful in photographing the hatching of the pod, as a part of the life cycle of the tick; but she did take photos of the pods on the roos.

Neither Margaret nor I have done a full study of these ‘tick pods’ or even summarised what is known about the life cycle of ticks, other than the general knowledge that there are at least four stages, eggs, pepper ticks (<0.3mm in size), ordinary ticks(~2mm in size) and mature ticks (~10mm in size). These are the ordinary kangaroo ticks, Ixodes australiensis. Electronic pictures of pepper ticks from Peter Fallon and Robert MacArthur appear on the Roleybushcare web site here. There is a good over-view of the development of the Kangaroo tick and others, including a life cycle diagram at http://www.karlmcmanusfoundation.org.au/ticks-in-oz. The tick doesn’t only visit roos, but is a pest of shingleback (bobtail) lizards, bandicoots and many other animals. I find it interesting that the mature form of the tick has a design (pattern) on the middle of the back.

The observations of Margaret Binns suggest that there may be a ‘pod state’ as a part of their life cycle, either regularly or in extraordinary circumstances. Also note that they can bite in all their stages. Their bite may be rather toxic, and the little ones bite more frequently and may be as toxic as the larger ones. The largest ticks are less likely to bite a human (apparently preferring roos), but if they do bite, they may make a person feel quite unwell for several days.The complete life cycle of the tick, from egg to mature form takes several years. It is not a good idea to remove them with kero or heat as it tends to leave their poisonous fluids inside you. However, unlike other species of tick, many claim they can be simply ‘scratched off’ without harm. Now the advice from CSIRO and Friends of Bibbulmun Track (Bibbulmun News, May-Aug 15, pg 7) is to use a ‘Freeze Stick’, used for warts; it is a spray containing ether (one brand is Wart-off) to freeze the tick. For the nymphs (pepper ticks) use a cream containing permethrin known as Elimite. Our experience is that local ticks (in all forms) have strong head attachments and (provided it is done with care) can be pulled straight off and usually will not leave their head embedded in the flesh. There are specialised tick tweezers available plus videos showing how to use them. Unfortunately, it is generally impractical to have the right materials available when you have a tick. But, if you know you have any significant reaction, please take precautions. It is silly but some people quite removed from the bush attract them and spend years fighting the reaction; others do much bush walking and have never had a tick.

Lastly, note the picture of a tick collected by Pat Scott on 20th November 2014, near to Wymond Rd. There is much unknown about these ticks. This tick seems less than fully mature; smaller(5mm maximum dimension without snout) and the design on the middle of the back is not complex; there is a whitish ellipse (reflection?) at the middle of the back, and a dorsal carapace. Ticks metamorphose and may change size many times a year; it can take many years (perhaps 10) for them to mature. Each stage has certain requirements even as to species of blood required. The tick shown is a near-to-adult or mature form, possibly a male.

Please note that this should be authored by Margaret Binns and Bill Scott. If Mark agrees, this should also be authored by Mark Harvey of the WA Museum. In any case, if Mark reviews the article, he should be so credited.